Method of operating pure oxygen wet oxidation systems

A method for startup, operation and shutdown of a wet oxidation apparatus which uses a flow of pure oxygen for oxidizing combustible substances, said apparatus including a reactor, valved means for introducing water and combustible substance into said reactor, valved means for introducing a flow of pure oxygen into said reactor, valved means for passing gaseous and liquid combustion products from said reactor, valved means for introducing a stream of purge water into oxygen introducing means, valved means for introducing cleaning solution into said oxygen introducing means, and valved means for purging said reactor with an inert diluent gas, said method comprising the steps of:

• initiating a potential for oxidation in said reactor prior to starting the flow of oxygen to said reactor, and maintaining the potential for oxidation until the flow of oxygen is stopped;
• starting a continuous purge of inert diluent gas into said reactor prior to starting the flow of oxygen, and continuing the addition or in situ generation of inert gas in the reactor until after the flow of oxygen is stopped;
• and cleaning the portion of the oxygen introducing means within said reactor with a cleaning solution and subsequently introducing a stream of purge water into oxygen introduction means prior to starting the flow of oxygen to said reactor, and continuing the flow of said purge water until after said flow of oxygen is stopped.